Pluto

(HOST) News headlines about Pluto grabbed the attention of millions. And its fall from planetary grace was debated by hundreds of scientists. But its discovery seventy-five years ago was a solitary affair. Commentator Allen Gilbert tells the story.

(GILBERT) I have a postcard from the Lowell Observatory in Flagstaff, Arizona. The card shows two photos of the nighttime sky. There is a tiny, tiny difference between the two images. The difference is the movement of one speck among the many other specks in the photo. It's nearly undetectable. Pinpointing that movement enabled the identification in 1930 of what -- up until recently -- was our ninth planet, Pluto.

This summer, teams of scientists debated Pluto's future. All this attention by panels of learned academics is in stark contrast to Pluto's discovery. That came about through the effort of one lonely man sitting night after night, peering into a giant telescope mounted at an observatory on an Arizona hilltop. Some nights were so cold at the Lowell Observatory that astronomer Clyde Tombaugh nearly died of hypothermia. The observatory building was constructed of local pine. The telescope was aimed by an ingenious system of axles, pulleys, and automobile tires.

The Lowell Observatory itself was the vision of one man: Percival Lowell. Percival Lowell was of the prominent New England family that owned the large mills in Lowell, Massachusetts. Percival's brother, A. Lawrence Lowell, was president of Harvard; his sister Amy Lowell a well-known poet. Percival was a rather, well, creative personality. Among other things, he fashioned himself an amateur astronomer. He accepted theories purported by an Italian astronomer of the time, Giovanni Schiaparelli, who said that markings on Mars were canals and were evidence of life on that planet. Lowell wrote several books on the subject. We owe the popularization of the term "Martians" to Lowell.

Backed by his family's money and standing, Percival Lowell decided he needed his own observatory to do his stargazing. He sent a team of men to scour the American southwest for the best site: a place with clear skies and little ground light. Flagstaff was the choice. Lowell moved there in 1894.

In addition to his belief that there was life on Mars, Lowell felt that there were more planets yet to be discovered in the solar system. Attired in a frock coat and cravat, Lowell spent hours gazing through the telescopes at his observatory. He died in 1916 without having found Pluto, but the observatory staff carried on his work. Tombaugh succeeded when he made the crucial discovery of movement among the images he saw in the night sky. Scientists of the time confirmed it as the long-sought ninth planet.

A competition was held to name the planet. Rejected were the names Zeus and Lowell, among others. Finally, an eleven-year-old English schoolgirl proposed Pluto.

The Lowell Observatory still operates, and it's open to visitors. The city of Flagstaff has pioneered restrictions on nighttime lighting to protect the observatory's views skyward. And Pluto, whether a planet or not, is said to bear a tribute to Lowell in its name. The first two letters, PL, are Percival Lowell's initials.

Allen Gilbert is a former journalist, teacher, and consultant currently serving as executive director of the ACLU of Vermont. He has a longtime interest in public policy issues.